Iminothiazolines, their production and use as herbicides, and intermediates for their production

ABSTRACT

There is disclosed an iminothiazoline compound of the formula: ##STR1## wherein R 1  is halogen, halo(lower)alkyl, halo(lower)alkoxy or halo(lower)alkylthio; R 2  is lower alkyl, chlorine, bromine or iodine; R 3  is (lower alkyl)carbonyl, (lower cycloalkyl)carbonyl, (lower cycloalkoxy)carbonyl, (lower alkoxy)carbonyl or (lower alkyl)sulfonyl, all of which are optionally substituted with at least one substituent selected from halogen, lower alkyl, lower alkoxy, lower cycloalkyl and lower cycloalkoxy; and R 4  is halogen. Also disclosed are a process for producing this compound, a herbicidal composition comprising this compound as an active ingredient, and a method for controlling undesired weeds by use of this compound as a herbicide.

This application is a divisional of application Ser. No. 07/933,110,filed on Aug. 21, 1992, U.S. Pat. No. 5,350,736 the entire contents ofwhich are hereby incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to iminothiazolines, their production anduse as herbicides, and intermediates for their production. Moreparticularly, it relates to iminothiazoline compounds having strongherbicidal potency and intermediate compounds for production of theiminothiazoline compounds.

BACKGROUND OF THE INVENTION

Certain kinds of iminothiazolidine derivatives are known to be useful asan active ingredient of herbicidal compositions (cf., EP-A-0349282).However, they can hardly be said to be satisfactory herbicides.

OBJECTS OF THE INVENTION

The present inventors have intensively studied to seek satisfactoryherbicides and found that particular iminothiazoline compounds havestrong herbicidal potency and some of them further exhibit noticeableselectivity between crop plants and weeds.

SUMMARY OF THE INVENTION

The present invention provides iminothiazoline compounds of the formula:##STR2## wherein R¹ is halogen, halo(lower)alkyl, halo(lower)alkoxy orhalo(lower)alkylthio; R² is lower alkyl, chlorine, bromine or iodine; R³is (lower alkyl)carbonyl, (lower cycloalkyl)carbonyl, (loweralkoxy)carbonyl, (lower cycloalkoxy)carbonyl or (lower alkyl)sulfonyl,all of which are optionally substituted with substituents which are thesame or different and are selected from halogen, lower alkyl, loweralkoxy, lower cycloalkyl and lower cycloalkoxy; and R⁴ is halogen; morespecifically, iminothiazoline compounds of the formula (I) wherein R¹ ishalogen, halo(C₁ -C₃)alkyl, halo(C₁ -C₃)alkoxy or halo(C₁ -C₃)alkylthio;R² is C₁ -C₂ alkyl chlorine bromine or iodine; R³ is C₁ -C₆alkylcarbonyl, C₃ -C₆ cycloalkylcarbonyl, C₁ -C₆ alkoxycarbonyl, C₃ -C₆cycloalkoxycarbonyl or C₁ -C₆ alkylsulfonyl, all of which are optionallysubstituted with substituents which are the same or different and areselected from halogen, C₁ -C₃ alkyl, C₁ -C₃ alkoxy, C₃ -C₆ cycloalkyland C₃ -C₆ cycloalkoxy; and R⁴ is halogen; an iminothiazoline compoundof the formula: ##STR3## wherein R¹ and R⁴ are each as defined above andR⁶ is hydrogen or methyl, which is an intermediate for the compound (I);a process for producing the iminothiazoline compound (IV); and aherbicidal composition comprising as an active ingredient the aboveiminothiazoline compounds (I).

DETAILED DESCRIPTION OF THE INVENTION

As used herein, the term "C_(n) -C_(m) " refers to the carbon number ofa group immediately following this term. In case of C₁ -C₆alkylcarbonyl, for instance, the term "C₁ -C₆ " indicates the carbonnumber of its alkyl portion and exclude that of its carbonyl portion.Also, a group substituted with a substituent preferably covers a groupbearing from 1 to 10 substituents which may be the same or different.

The iminothiazoline compounds (I) produce generally strong herbicidalactivity against a wide variety of weeds including broad-leaved weedsand Graminaceous weeds in agricultural plowed fields by foliar or soiltreatment without producing any material phytotoxicity to crop plants.Examples of the broad-leaved weeds include common purslane (Portulacaoleracea), common chickweed (Stellaria media), common lambsquarters(Chenopodium album), redroot pigweed (Amaranthus retroflexus), radish(Raphanus sativus), wild mustard (Sinapis arvensis), shepherdspurse(Capsella bursa-pastoris), hemp sesbania (Sesbania exaltata), sicklepod(Cassia obtusifolia), velvetleaf (Abutilon theophrasti), prickly sida(Sida spinosa), field pansy (Viola arvensis), catchweed bedstraw (Galiumaparine), ivyleaf morningglory (Ipomoea hederacea), tall morningglory(Ipomoea purpurea), field bindweed (Convolvulus arvensis), purpledeadnettle (Lamium purpureum), henbit (Lamium amplexicaure), jimsonweed(Datura stramonium), black nightshade (Solanum nigrum), persianspeedwell (Veronica persica), common cocklebur (Xanthium pensylvanicum),common sunflower (Helianthus annuus), scentless chamomile (Matricariaperforata) and corn marigold (Chrysanthemum segetum) . Examples ofGraminaceous weeds include Japanese millet (Echinochloa frumentacea),barnyardgrass (Echinochloa crus-galli), green foxtail (Setaria viridis),yellow foxtail (Setaria glauca), southern crabgrass (Digitariaciliaris), large crabgrass (Digitaria sanguinalis), annual bluegrass(Poa annua), blackgrass (Alopecurus myosuroides), oats (Arena sativa),wild oats (Avena fatua), johnsongrass (Sorghum halepense ), quackgrass(Agropyron repens ), downy brome (Bromus tectorum), giant foxtail(Setaria faberi), fall panicum (Panicum dichotomiflorum), shattercane(Sorghum bicolor) and bermudagrass (Cynodon dactylon) . Some of theiminothiazoline compounds (I) have the advantage of showing no materialchemical injury to various agricultural crops such as corn, wheat,barley, rice plant, soybean, cotton and sugar beet.

The iminothiazoline compounds (I) are also effective in exterminatingpaddy field weeds including Graminaceous weeds such as barnyardgrass(Echinochloa oryzicola), broad-leaved weeds such as commonfalsepimpernel (Lindernia procumbens), indian toothcup (Rotala indica),waterwort (Elatine triandra) and Ammannia multiflora, Cyperaceous weedssuch as umbrella sedge (Cyperus difformis), hardstem bulrush (Scirpusjuncoides), needle spikerush (Eleocharis acicularis) and water nutgrass(Cyperus serotinus), and others such as monochoria (Monochoriavaginalis) and arrowhead (Sagittaria pygmaea) . Some of theiminothiazoline compounds (I) have the advantage of showing nophytotoxicity to rice plants on flooding treatment.

Among the iminothiazoline compounds (I), preferred are those wherein R¹is halo (C₁ -C₃) alkyl, more preferably trifluoromethyl; those whereinR² is methyl or ethyl; those wherein R³ is C₁ -C₆ alkylcarbonyl or C₃-C₆ cycloalkyl-carbonyl, both of which are optionally substituted withat least one substituent selected from halogen, C₁ -C₃ alkyl and C₁ -C₃alkoxy; and those wherein R⁴ is present at the para position, moreparticularly fluorine at the para position.

The iminothiazoline compounds (I) can be produced by various procedures,of which typical examples are shown in the following schemes I to III.##STR4## wherein R¹, R², R³, R⁴ and R⁶ are each as defined above; R⁷ is(C₁ -C₆ alkyl) carbonyl; R⁸ and R⁹, which are different, are C₁ -C₆alkyl; R¹⁰ is chlorine, bromine or iodine; and X and Y are each bromineor iodine.

Procedures for production of the iminothiazoline compounds (I) as shownin the above schemes I to III will hereinafter be explained in detail.

Procedure (A):

The iminothiazoline compound (I) wherein is R² is methyl or ethyl can beobtained by reacting the iminithiazolidine compound (II) with a base oracid.

This reaction is usually carried out in a solvent at a temperature ofabout 0° to 200° C. for a period of 1 to 30 hours. The base or acid isused at a proportion of 1 to 100 equivalents to one equivalent of thecompound (II).

As the solvent, there may be exemplified aliphatic hydrocarbons (e.g.,hexane, heptane), aromatic hydrocarbons (e.g., benzene, toluene,xylene), ethers (e.g., diisopropyl ether, dioxane, tetrahydrofuran,diethylene glycol dimethyl ether), alcohols (e.g., methanol, ethanol,isopropanol, t-butanol, octanol, cyclohexanol, 2-methoxyethanol,diethylene glycol, glycerin), acid amides (e.g, N,N-dimethylformamide)and sulfur compounds (e.g, dimethylsulfoxide, sulforan). These solventsmay be used solely or in combination. Examples of the base are inorganicbases (e.g., sodium hydroxide, potassium hydroxide, sodium carbonate,potassium carbonate, sodium hydride) and alkali metal alkoxides (e.g.,sodium methoxide, sodium ethoxide, potassium t-butoxide, sodiumt-butoxide). Examples of the acid are sulfuric acid and hydrochloricacid.

After completion of the reaction, the reaction mixture may be subjectedto ordinary post-treatment in a per se conventional manner such asextraction with an organic solvent and concentration. If necessary, anypurification method (e.g., chromatography, recrystallization) may befurther utilized to give the objective compound (I), i.e., compound(I-1).

Procedure (B):

The iminothiazoline compound (I) wherein R² is methyl or ethyl can beobtained by the reaction of the iminothiazoline compound (IV) with anacid chloride (V) or acid anhydride (XIV) in the presence of a base, orby the reaction of the iminothiazoline compound (IV) with an acid (VI).

This reaction is usually carried out in a solvent at a temperature ofabout 0° to 200° C. for a period of 1 to 30 hours. The acid chloride(V), acid anhydride (XIV) or acid (VI) may be used at a proportion of 1to 10 equivalents to one equivalent of the compound (IV), and the basemay be used at a proportion of 1 to 50 equivalents to one equivalent ofthe compound (IV). When the reaction is carried with the acid (VI), acondensing agent such as dicyclohexylcarbodiimide is usually used at aproportion of 1 to 10 equivalents to one equivalent of the compound(IV).

As the solvent, there may be exemplified aliphatic hydrocarbons (e.g.,hexane, heptane, ligroin, petroleum ether), aromatic hydrocarbons (e.g.,benzene, toluene, xylene), halogenated hydrocarbons (e.g., chloroform,carbon tetrachloride, dichloroethane, chlorobenzene, dichlorobenzene),ethers (e.g., diethyl ether, diisopropyl ether, dioxane,tetrahydrofuran, diethylene glycol dimethyl ether), ketones (e.g.,acetone, methyl ethyl ketone, methyl isobutyl ketone, isophorone,cyclohexanone), esters (e.g., ethyl formate, ethyl acetate, butylacetate, diethyl carbonate), nitro compounds (e.g., nitroethane,nitrobenzene), nitriles (e.g., acetonitrile, isobutyronitrile), tertiaryamines (e.g., pyridine, triethylamine, N,N-diethylaniline,tributylamine, N-methylmorpholine), acid amides (e.g.,N,N-dimethylformamide) and sulfur compounds (e.g, dimethylsulfoxide,sulforan). These solvents may be used solely or in combination. Examplesof the base are organic bases (e.g., pyridine, triethylamine,N,N-diethylaniline) or inorganic bases (e.g., potassium carbonate,sodium hydroxide).

After completion of the reaction, the reaction mixture may be subjectedto ordinary post-treatment in the same manner as described in Procedure(A) to give the objective compound (I), i.e., compound (I-1).

Procedure (C):

The iminothiazoline compound (I) wherein R² is methyl or ethyl and R³ is--CO--OR⁹ can be produced by reacting the iminothiazoline compound (I-5)with the alcohol (XV) in the presence of a base.

This reaction is usually carried out in a solvent at a temperature ofabout 10° to 200° C. for a period of 1 to 100 hours. The alcohol (XV)and base may be used at proportions of 1 to 10 equivalents and 0.5 to 50equivalents to one equivalent of the compound (I-5), respectively.

As the solvent, there may be exemplified aliphatic hydrocarbons (e.g.,hexane, heptane, ligroin), aromatic hydrocarbons (e.g., benzene,toluene, xylene), ethers (e.g., diethyl ether, diisopropyl ether,dioxane, tetrahydrofuran, diethylene glycol dimethyl ether), alcohols(e.g., methanol, ethanol, isopropanol, t-butanol, octanol, cyclohexanol,2-methoxyethanol, diethylene glycol, glycerin), acid amides (e.g,N,N-dimethylformamide), sulfur compounds (e.g, dimethylsulfoxide,sulforan) and water. These solvents may be used solely or incombination. Examples of the base are inorganic bases (e.g., sodiumhydroxide, potassium hydroxide) and alkali metal alkoxides (e.g., sodiummethoxide, sodium ethoxide).

After completion of the reaction, the reaction mixture may be subjectedto ordinary post-treatment in the same manner as described in Procedure(A) to give the objective compound (I), i.e., compound (I-2).

Procedure (D):

The iminothiazoline compound (I) wherein R² is chlorine, bromine oriodine is prepared by reacting the iminothiazolidine compound (VII) witha chlorinating, brominating or iodinating agent.

This reaction is usually carried out in a solvent at a temperature ofabout 50° to 150° C. for a period of 2 to 100 hours. The chlorinating,brominating or iodinating agent may be used at a proportion of 1 to 10equivalents to one equivalent of the compound (VII).

Examples of the solvent are aliphatic hydrocarbons (e.g., hexane,heptane), aromatic hydrocarbons (e.g., benzene, toluene, xylene),halogenated hydrocarbons (e.g., chloroform, carbon tetrachloride,dichloroethane) and ethers (e.g., diisopropyl ether, dioxane,tetrahydrofuran, diethylene glycol dimethyl ether). These solvents maybe used solely or in combination. As the chlorinating, brominating oriodinating agent, there may be exemplified N-chlorosuccinimide,N-bromosuccinimide and N-iodosuccinimide.

After completion of the reaction, the reaction mixture may be subjectedto ordinary post-treatment in the same manner as described in Procedure(A) to give the objective compound (I), i.e., compound (I-3).

Procedure (E):

The iminothiazoline compound (I) wherein R² is chlorine, bromine oriodine can be obtained by reacting the iminothiazoline compound (VIII)with a chlorinating, brominating or iodinating agent.

This reaction is usually carried out in a solvent at a temperature ofabout 50° to 150° C. for a period of 2 to 100 hours. The chlorinating,brominating or iodinating agent may be used at a proportion of 1 to 10equivalents to one equivalent of the compound (VIII).

Examples of the solvent and chlorinating, brominating or iodinatingagent may be those as exemplified in Procedure (D).

After completion of the reaction, the reaction mixture may be subjectedto ordinary post-treatment in the same manner as described in Procedure(A) to give the objective compound (I), i.e., compound (I-3).

Typical examples of the iminothiazoline compounds (I) produced by theabove procedure are shown in Table 1.

                  TABLE 1                                                         ______________________________________                                         ##STR5##                      (I)                                            R.sup.1   R.sup.2 R.sup.3            R.sup.4                                  ______________________________________                                        CF.sub.3  CH.sub.3                                                                              COCH.sub.3         4-F                                      CF.sub.3  CH.sub.3                                                                              COCF.sub.3         4-F                                      CF.sub.3  CH.sub.3                                                                              CO-i-C.sub.3 H.sub.7                                                                             4-F                                      CF.sub.3  CH.sub.3                                                                              CO.sub.2 -i-C.sub.3 H.sub.7                                                                      4-F                                      CF.sub.3  CH.sub.3                                                                              COCF.sub.3         6-F                                      CF.sub.3  CH.sub.3                                                                              CO.sub.2 -i-C.sub.3 H.sub.7                                                                      6-F                                      CF.sub.3  CH.sub.3                                                                              COCH.sub.3         4-Cl                                     CF.sub.3  CH.sub.3                                                                              COCF.sub.3         4-Cl                                     CF.sub.3  CH.sub.3                                                                               ##STR6##          4-Cl                                     Cl        C.sub.2 H.sub.5                                                                        ##STR7##          4-F                                      Br        Br      CO.sub.2 -n-C.sub.4 H.sub.9                                                                      5-F                                      CF.sub.3  C.sub.2 H.sub.5                                                                       COCH.sub.2 OCH.sub.3                                                                             2-F                                      OCF.sub.3 CH.sub.3                                                                              COCF.sub.3         4-F                                      SCF.sub.3 CH.sub.3                                                                              COCF.sub.3         4-F                                      OCHF.sub. 2                                                                             Br                                                                                     ##STR8##          4-F                                      CF.sub.3  Cl      CO-n-C.sub.3 H.sub.7                                                                             4-F                                      CF.sub.3  I       CO-n-C.sub.5 H.sub.11                                                                            2-F                                      CF.sub.3  CH.sub.3                                                                               ##STR9##          4-Cl                                     CF.sub.3  CH.sub.3                                                                              COCHF.sub.2        4-F                                      CF.sub.3  C.sub.2 H.sub.5                                                                       COCH.sub.3         4-F                                      CF.sub.3  C.sub.2 H.sub.5                                                                       COCF.sub.3         4-F                                      CF.sub.3  C.sub.2 H.sub.5                                                                       COCHF.sub.2        4-F                                      Cl        Br      CO.sub.2 C.sub.2 H.sub.5                                                                         4-F                                      CF.sub.3  CH.sub.3                                                                              COCH.sub.2 -t-C.sub.4 H.sub.9                                                                    4-F                                      CF.sub.3  CH.sub.3                                                                              CO-n-C.sub.5 H.sub.11                                                                            4-F                                      CF.sub.3  CH.sub.3                                                                              COCH.sub.2 CH.sub.2 Cl                                                                           4-F                                      CF.sub.3  CH.sub.3                                                                              COCH.sub.2 OCH.sub.3                                                                             4-F                                      CF.sub.3  CH.sub.3                                                                               ##STR10##         4-Cl                                     CF.sub.3  CH.sub.3                                                                              COC.sub.3 H.sub.7  4-Cl                                     CF.sub.3  CH.sub.3                                                                              SO.sub.2 CF.sub.3  4-Cl                                     CF.sub.3  CH.sub.3                                                                              CO.sub.2 -n-C.sub.6 H.sub.13                                                                     4-F                                      CF.sub.3  CH.sub.3                                                                               ##STR11##         4-F                                      CF.sub.3  CH.sub.3                                                                              SO.sub.2 CH.sub.3  4-Cl                                     CF.sub.3  CH.sub.3                                                                              CO.sub.2 CH.sub.2 CH.sub.2 OCH.sub.3                                                             4-Cl                                     CF.sub.3 S                                                                              CH.sub.3                                                                               ##STR12##         4-F                                      CHF.sub.2 O                                                                             CH.sub.3                                                                               ##STR13##         4-F                                      CF.sub.3  CH.sub.3                                                                               ##STR14##         4-F                                      Cl        Br      CO.sub.2 -n-C.sub.6 H.sub.13                                                                     4-F                                      Br        CH.sub.3                                                                              CO.sub.2 -i-C.sub.3 H.sub.7                                                                      4-Cl                                     CF.sub.3  CH.sub.3                                                                              CO.sub.2 C.sub.4 H.sub.9                                                                         4-Cl                                     CF.sub.3  CH.sub.3                                                                               ##STR15##         4-Cl                                     CF.sub.3  C.sub.2 H.sub.5                                                                        ##STR16##         4-F                                      CF.sub.3  CH.sub.3                                                                               ##STR17##         4-F                                      CF.sub.3  CH.sub.3                                                                              CO-n-C.sub.6 H.sub.13                                                                            4-F                                      C.sub.2 F.sub.5                                                                         CH.sub.3                                                                              CO-n-C.sub.3 H.sub.7                                                                             4-F                                      CF.sub.2 HCF.sub.2 O                                                                    CH.sub.3                                                                              COC.sub.2 H.sub.5  4-F                                      C.sub.2 F.sub.5 S                                                                       CH.sub.3                                                                              COCH.sub.3         4-F                                      CF.sub.3  CH.sub.3                                                                              SO.sub.2 C.sub.3 H.sub.7                                                                         4-F                                      CF.sub.3  CH.sub.3                                                                               ##STR18##         4-F                                      CF.sub.3  CH.sub.3                                                                               ##STR19##         4-F                                      ______________________________________                                    

It should be noted that the iminothiazoline compounds (I) include theirstereo isomers having herbicidal activity.

The iminothiazoline compounds (II) can be obtained by reacting theaniline derivatives (IX) with the isothiocyanate (X) to give thethiourea (XI) which is then converted into the compound (II) (Scheme I).

This reaction is usually carried out in a solvent at a temperature ofabout 0° to 200° C. for a period of 1 to 30 hours. The compound (X) maybe used at proportions of 1 to 5 equivalents to one equivalent of thecompound (IX).

As the solvent, there may be exemplified aliphatic hydrocarbons (e.g.,hexane, heptane, ligroin, petroleum ether), aromatic hydrocarbons (e.g.,benzene, toluene, xylene), halogenated hydrocarbons (e.g., chloroform,carbon tetrachloride, dichloroethane, chlorobenzene, dichlorobenzene),ethers (e.g., diethyl ether, diisopropyl ether, dioxane,tetrahydrofuran, diethylene glycol dimethyl ether), ketones (e.g.,acetone, methyl ethyl ketone, methyl isobutyl ketone, isophorone,cyclohexanone), nitro compounds (e.g., nitroethane, nitrobenzene),tertiary amines (e.g., N,N-diethylaniline, tributylamine,N-methylmorpholine), acid amides (e.g., N,N-dimethylformamide) andsulfur compounds (e.g., dimethylsulfoxide, sulforan). These solvents maybe used solely or in combination. As the catalyst which may be used forconverting the compound (XI) into the compound (II), there may beexemplified acids (e.g., trifluoroacetic acid, sulfuric acid) and bases(e.g., sodium methylate).

After completion of the reaction, the reaction mixture may be subjectedto ordinary post-treatment in the same manner as described in Procedure(A) to give the objective compound (II).

According to this method, the compound (I-1) can be directly obtainedwithout isolation of the compound (II).

The compound (II) can also be produced by reacting the iminothiazolidinecompound (III) with a base.

This reaction is usually carried out in a solvent at a temperature ofabout 0° to 200° C. for a period of 1 to 30 hours. The base may be usedat proportions of 1 to 50 equivalents to one equivalent of the compound(III).

As the solvent, there may be exemplified aliphatic hydrocarbons (e.g.,hexane, heptane, ligroin), aromatic hydrocarbons (e.g., benzene,toluene, xylene), ethers (e.g., diethyl ether, diisopropyl ether,dioxane, tetrahydrofuran, diethylene glycol dimethyl ether), alcohols(e.g., methanol, ethanol, isopropanol, t-butanol, octanol, cyclohexanol,2-methoxyethanol, diethylene glycol, glycerin), acid amides (e.g.,formamide, N,N-dimethylformamide, acetamide) and sulfur compounds (e.g.,dimethylsulfoxide, sulforan). These solvents may be used solely or incombination. Examples of the base may be inorganic bases (e.g., sodiumhydroxide, potassium hydroxide) and alkali metal alkoxides (e.g., sodiummethoxide, sodium ethoxide, sodium t-butoxide).

After completion of the reaction, the reaction mixture may be subjectedto ordinary post-treatment in the same manner as described in Procedure(A) to give the objective compound (II).

According to this method, the compound (I-1) can also be directlyobtained without isolation of the compound (II).

The compound (VIII) can be obtained by reacting the iminothiazolinecompound (I-3) wherein R¹⁰ is bromine with a reducing agent such astributyltin hydride.

This reaction is usually carried out in a solvent at a temperature ofabout 0° to 200° C. for a period of 1 to 30 hours. The reducing agentmay be used at proportions of 1 to 100 equivalents to one equivalent ofthe compound (I-3) wherein R¹⁰ is bromine.

There may be used as the solvent aliphatic hydrocarbons (e.g., hexane,heptane, ligroin, petroleum ether), aromatic hydrocarbons (e.g.,benzene, toluene, xylene), ethers (e.g., diethyl ether, diisopropylether, dioxane, tetrahydrofuran, diethylene glycol dimethyl ether),ketones (e.g., acetone, methyl ethyl ketone, methyl isobutyl ketone,isophorone, cyclohexanone), esters (e.g., ethyl formate, ethyl acetate,butyl acetate, diethyl carbonate), nitro compounds (e.g., nitroethane,nitrobenzene), nitriles (e.g., acetonitrile, isobutyronitrile), acidamides (e.g., N,N-dimethylformamide) and sulfur compounds (e.g.,dimethylsulfoxide, sulforan). These solvents may be used solely or incombination.

After completion of the reaction, the reaction mixture may be subjectedto ordinary post-treatment in the same manner as described in Procedure(A).

The iminothiazolidine compound (III) may be produced by the method asdescribed in J. Am. Chem. Soc., 1079(1984). That is, the compound (III)can be obtained by reacting the aniline compound (XVI) with theisothiocyanate compound (X) to give the thiourea compound (XVII) whichis then treated with a halogenating agent.

The iminothiazolidine compound (VII) may be obtained by reacting thethiourea (XXVI) with the halide (XXVII) to give the iminothiazoline(XXVIII) which is then treated with the compound (V), (XIV) or (VI)under the same condition as described in Procedure (B).

The iminothiazolidine compound (VII) can also be produced by treatingthe thiourea (XXX) with the halide (XXVII).

The compound (IV) can be obtained by hydrolyzing the compound (I-4) withan acid.

This reaction is usually carried out in a solvent at a temperature ofabout 30° to 200° C. for a period of 1 to 100 hours. The acid may beused at proportions of 1 to 1000 equivalents to one equivalent of thecompound (I-4).

Examples of the solvent are aromatic hydrocarbons (e.g., benzene,toluene, xylene), ethers (e.g., diethyl ether, diisopropyl ether,dioxane, tetrahydrofuran, diethylene glycol dimethyl ether), fatty acids(e.g., formic acid, acetic acid, oleic acid), alcohols (e.g., methanol,ethanol, isopropanol, t-butanol, octanol, cyclohexanol,2-methoxyethanol, diethylene glycol, glycerin) and water. These solventsmay be used solely or in combination. Examples of the acid are sulfuricacid and hydrochloric acid which is preferred.

After completion of the reaction, the reaction mixture may be subjectedto ordinary post-treatment in the same manner as described in Procedure(A) to give the compound (IV).

Alternatively, after completion of the reaction, the reaction mixturemay be concentrated under reduced pressure to give the base of thecompound (IV). Although the compound (IV) is obtained by neutralizationof the base, it is possible to use the base as such in Procedure (B)without converting into the compound (IV).

Typical examples of the compound (IV) obtained by the above procedureare shown in Table 2.

                  TABLE 2                                                         ______________________________________                                         ##STR20##                    (IV)                                            R.sup.1          R.sup.6     R.sup.4                                          ______________________________________                                        CF.sub.3         H           4-F                                              CF.sub.3         CH.sub.3    4-F                                              CF.sub.3         H           5-F                                              CF.sub.3         CH.sub.3    5-F                                              CF.sub.3         H           4-Cl                                             CF.sub.3         H           2-F                                              F                H           6-F                                              Cl               H           5-F                                              Br               CH.sub.3    4-F                                              OCF.sub.3        H           4-F                                              ______________________________________                                    

For the practical usage of the iminothiazoline compounds (I), they areusually formulated with conventional solid or liquid carriers ordiluents as well as surface active agents, or other auxiliary agentsinto conventional formulations such as emulsifiable concentrates,wettable powders, flowables, granules and water-dispersible granules.

These formulations contain the iminothiazoline compounds (I) as anactive ingredient at a content within the range of about 0.02% to 90% byweight, preferably of about 0.05% to 80% by weight.

Examples of the solid carrier or diluent are fine powders or granules ofkaolin clay, attapulgite clay, bentonite, terra alba, pyrophyllite,talc, diatomaceous earth, calcite, walnut shell powders, urea, ammoniumsulfate and synthetic hydrous silica. As the liquid carrier or diluent,there may be exemplified aromatic hydrocarbons (e.g., xylene,methylnaphthalene), alcohols (e.g., isopropanol, ethylene glycol,2-ethoxyethanol), ketones (e.g., acetone, cyclohexanone, isophorone),vegetable oils (e.g., soybean oil, cotton seed oil), dimethylsulfoxide,N,N-dimethylformamide, acetonitrile and water.

The surface active agent used for emulsification, dispersing orspreading may be of any type, for instance, either anionic or non-ionic.Examples of the surface active agent include alkylsulfates,alkylsulfonates, alkylarylsulfonates, dialkylsulfosuccinates, phosphatesof polyoxyethylenealkylaryl ethers, polyoxyethylene alkyl ethers,polyoxyethylene alkylaryl ethers, polyoxyethylene polyoxypropylene blockcopolymer, sorbitan fatty acid esters and polyoxyethylene sorbitan fattyacid esters. Examples of the auxiliary agent include ligninsulfonates,alginates, polyvinyl alcohol, gum arabic, CMC (carboxymethyl cellulose)and PAP (isopropyl acid phosphate).

The iminothiazoline compounds (I) are usually formulated in any suitableformulation and used for pre-emergence or post-emergence control ofundesired weeds by soil treatment, foliar treatment or flood fallowingtreatment. These treatments include application to the soil surfaceprior to or after planting, incorporation into the soil prior toplanting or transplanting, and the like. The foliar treatment may beeffected by spraying a herbicidal composition containing theiminothiazoline compounds (I) over the top of plants. It may also beapplied directly to the weeds if care must be taken to keep the chemicaloff the crop foliage.

The dosage of the iminothiazoline compounds (I) may vary depending onthe prevailing weather conditions, formulation used, prevailing season,mode of application, soil involved, crop and weed species, and the like.Usually, however, the dosage is from about 10 to 5000 grams, preferablyfrom about 20 to 2000 grams, of the active ingredient per hectare. Theherbicidal composition thus formulated in the form of an emulsifiableconcentrate, wettable powder or flowable may usually be employed bydiluting it with water at a volume of about 100 to 1000 liters perhectare, if necessary, with addition of an auxiliary agent such as aspreading agent. The herbicidal composition formulated in the form ofgranules may usually be applied as such without dilution.

Examples of the spreading agent include, in addition to the surfaceactive agents as described above, polyoxyethylene resin acid (ester),ligninsulfonate, abietylenic acid salt, dinaphthylmethanedisulfonate andparaffin.

The iminothiazoline compounds (I) are useful as a herbicide to beemployed for paddy filed, crop field, orchards, pasture land, lawns,forests and non-agricultural fields. Further, the iminothiazolinecompounds (I) may also be used together with any other herbicide toimprove their herbicidal activity, and in some cases, synergisticeffects can be expected. Furthermore, these compounds may be applied incombination with insecticides, acaricides, nematocides, fungicides,plant growth regulators, fertilizers, soil improvers and the like.

The present invention will be explained in more detail by way ofPreparation Examples, Reference Examples, Formulation Examples and TestExamples, to which however the invention is not limited in any way.

Practical and presently preferred embodiments for production of theiminothiazoline compounds (I) are illustrated in the following examples.

Preparation Example 1

Procedure (A)

A mixture of acetyl chloride (2.75 g) and acetonitrile (70 ml) wascooled at 0° C., and potassium thiocyanate (3.57 g) was added to thismixture, followed by stirring at room temperature for 6 hours. Aftercooling at 0° C., 3-trifluoromethyl-4-fluoro-N-propalgylaniline (7.6 g)was added to the reaction mixture and stirring was continued at roomtemperature for 3 hours.

After removal of the solvent under reduced pressure, the concentratedresidue was extracted with ethyl acetate (300 ml), and the extract waswashed with water. After removal of the solvent, crystallines (8.5 g)were obtained. These crystallines were slowly added to sulfuric acid (25ml) at 0° C., and stirring was continued at 0° C. for 0.5 hours, then atroom temperature for 1 hour. The reaction solution was poured into icewater, and the mixture was neutralized with aqueous sodium hydroxide togive 8 g of2-acetylimino-3-(3-trifluoromethyl-4-fluorophenyl)-5-methylthiazoline(Compound No. 1). m.p., 179.0° C.

Preparation Example 2

Procedure (B)

To a mixture of2-imino-3-(3-trifluoromethyl-4-fluorophenyl)-5-methylthiazolinehydrochloride (0.62 g) and triethylamine (0.61 g) in ethyl acetate (20ml), trifluoroacetic acid anhydride (0.42 g) was added at 0° C. Afterstirring at room temperature for 3 hours, the residue was extracted withethyl acetate (100 ml), and the extract was washed with water. Thesolvent was removed under reduced pressure to give crystallines. Thesecrystallines were washed with hexane to give 0.45 g of2-trifluoroacetylimino-3-(3-trifluoromethyl-4-fluorophenyl)-5-methylthiazoline(Compound No.2). m.p., 119.4° C.

In the same manner as above, the iminothiazoline compounds (I) as shownin Table 3 were obtained.

                  TABLE 3                                                         ______________________________________                                         ##STR21##                     (I)                                            Compound                                  m.p.                                No.      R.sup.1                                                                              R.sup.2 R.sup.3     R.sup.4                                                                             (°C.)                        ______________________________________                                         1       CF.sub.3                                                                             CH.sub.3                                                                              COCH.sub.3  4-F   179.0                                2       CF.sub.3                                                                             CH.sub.3                                                                              COCF.sub.3  4-F   119.4                                3       CF.sub.3                                                                             CH.sub.3                                                                              CO-i-C.sub.3 H.sub.7                                                                      4-F   133.2                                4       CF.sub.3                                                                             CH.sub.3                                                                              CO.sub.2 -i-C.sub.3 H.sub.7                                                               4-F   130.8                                5       CF.sub.3                                                                             CH.sub.3                                                                              COCF.sub.3  6-F   144.7                                6       CF.sub.3                                                                             CH.sub.3                                                                              CO.sub.2 -i-C.sub.3 H.sub.7                                                               6-F   158.5                                7       CF.sub.3                                                                             CH.sub.3                                                                              COCH.sub.3  4-Cl  187.9                                8       CF.sub.3                                                                             CH.sub.3                                                                              COCF.sub.3  4-Cl  134.2                                9       CF.sub.3                                                                             CH.sub.3                                                                               ##STR22##  4-Cl  166.2                               10       CF.sub.3                                                                             CH.sub.3                                                                              COCHF.sub.2 4-F   139.9                               11       CF.sub.3                                                                             C.sub.2 H.sub.5                                                                       COCH.sub.3  4-F   131.4                               12       CF.sub.3                                                                             C.sub.2 H.sub.5                                                                       COCF.sub.3  4-F    84.6                               13       CF.sub.3                                                                             C.sub.2 H.sub.5                                                                       COCHF.sub.2 4-F   117.0                               14       Cl     Br      CO.sub.2 C.sub.2 H.sub.5                                                                  4-F   224.1                               15       CF.sub.3                                                                             CH.sub.3                                                                              COCH.sub.2 -t-C.sub.4 H.sub.9                                                             4-F   129.3                               16       CF.sub.3                                                                             CH.sub.3                                                                              CO-n-C.sub.5 H.sub.11                                                                     4-F    46.3                               17       CF.sub.3                                                                             CH.sub.3                                                                              COCH.sub.2 CH.sub.2 Cl                                                                    4-F    35.0                               18       CF.sub.3                                                                             CH.sub.3                                                                              COCH.sub.2 OCH.sub.3                                                                      4-F   121.5                               19       CF.sub.3                                                                             CH.sub.3                                                                               ##STR23##  4-Cl  103.0                               20       CF.sub.3                                                                             CH.sub.3                                                                              COC.sub.3 F.sub.7                                                                         4-Cl   87.7                               21       CF.sub.3                                                                             CH.sub.3                                                                              SO.sub.2 CF.sub.3                                                                         4-Cl  150.0                               22       CF.sub.3                                                                             CH.sub.3                                                                              CO.sub.2 -n-C.sub.6 H.sub.13                                                              4-F   oil                                 23       CF.sub.3                                                                             CH.sub.3                                                                               ##STR24##  4-F   134.4                               24       CF.sub.3                                                                             CH.sub.3                                                                              SO.sub.2 CH.sub.3                                                                         4-Cl  144.2                               25       CF.sub.3                                                                             CH.sub.3                                                                              CO.sub.2 CH.sub.2 CH.sub.2 OCH.sub.3                                                      4-Cl  112.1                               ______________________________________                                    

The compounds (1) and (7) were produced according to the method ofPreparation Example 1, whereas the method of Preparation Example 2 wasused for production of the other compounds.

Preparation Example 3

(i) A mixture of2-acetylimino-3-(3-trifluoromethyl-4-fluorophenyl)-5-methylthiazoline(3.5 g) and hydrochloric acid (36%, 3.5 ml) in ethanol-water (35 ml) wasrefluxed for 3 hours. After cooling, the solvent was removed underreduced pressure, and the residue was isolated and washed with a littleamount of iso-propanol and hexane to give 2.8 g of3-(3-trifluoromethyl-4-fluorophenyl)-5-methyl-2-iminothiazolinehydrochloride (compound (i)).

(ii) To a mixture of ethyl acetate (50 ml) and aqueous potassiumcarbonate (20 ml),3-(3-trifluoromethyl-4-fluorophenyl)-5-methyl-2-iminothiazolinehydrochloride (1 g) was added; and the mixture was stirred. The organiclayer was isolated and dried over anhydrous magnesium sulfate. Thesolvent was removed under reduced pressure to give 0.7 g of3-(3-trifluoromethyl-4-fluorophenyl)-5-methyl-2-iminothiazoline as anoil.

In the same manner as above, the iminothiazoline compounds (IV) as shownin Table 4 were obtained.

                  TABLE 4                                                         ______________________________________                                        Compound                                                                      No.      R.sup.1  R.sup.4  R.sup.6                                                                            .sup.1 H-NMR/d.sup.6 -DMSO                    ______________________________________                                        i        CF.sub.3 4-F      H    10.1   (bs, 2H)                                                               8.3-7.5                                                                              (m, 3H)                                                                7.3    (s, 1H)                                                                2.3    (s, 3H)                                ii       CF.sub.3 4-Cl     H    10.1   (bs, 2H)                                                               8.2-7.7                                                                              (m, 3H)                                                                7.3    (s, 1H)                                                                2.3    (s, 3H)                                ______________________________________                                    

The following illustrates practical embodiments of the herbicidalcomposition according to the present invention wherein parts are byweight. The compound number of the active ingredient corresponds to thatof Table 3.

Formulation Example 1

Fifty parts of any one of Compound Nos. 1 to 21 and 23 to 25, 3 parts ofcalcium ligninsulfonate, 2 parts of sodium laurylsulfate and 45 parts ofsynthetic hydrous silica are well mixed while being powdered to obtainwettable powder.

Formulation Example 2

Five parts of any one of Compound Nos. 1 to 25, parts of "Toxanone P8L®"(commercially available surface active agent; Sanyo Kasei K. K.) and 80parts of cyclohexanone are well mixed to obtain emulsifiableconcentrate.

Formulation Example 3

Two parts of any one of Compound Nos. 1 to 21 and 23 to 25, 1 part ofsynthetic hydrous silica, 2 parts of calcium ligninsulfonate, 30 partsof bentonite and 65 parts of kaolin clay are well mixed while beingpowdered. The mixture is then kneaded with water, granulated and driedto obtain granules.

Formulation Example 4

Twenty-five parts of any one of Compound Nos. 1 to 21 and 23 to 25 aremixed with 3 parts of polyoxyethylene sorbitan monooleate, 3 parts ofcarboxymethyl cellulose (CMC) and 69 parts of water and pulverized untilthe particle size of the mixture becomes less than 5 microns to obtain asuspension.

The biological data of the iminothiazoline compound (I) as the herbicidewill be illustrated in the following Test Examples wherein thephytotoxicity to crop plants and the herbicidal activity on weeds weredetermined by visual observation as to the degree of germination as wellas the growth inhibition and rated with an index 0, 1, 2, 3, 4, 5, 6, 7,8, 9 or 10, the numeral "0" indicating no material difference as seen incomparison with the untreated plants and the numeral "10" indicating thecomplete inhibition or death of the test plants. The compound number inthe biological data corresponds to that shown in Table 3.

The compounds as shown in Table 5 were used for comparison.

                  TABLE 5                                                         ______________________________________                                        Com-                                                                          pound                                                                         No.    Structure             Remarks                                          ______________________________________                                                ##STR25##            Benthiocarb (commercially available herbicide                                 )                                                B                                                                                     ##STR26##            EP-A-0349282                                     C                                                                                     ##STR27##            EP-A-0349282                                     ______________________________________                                    

Test Example 1

Cylindrical plastic pots (diameter, 10 cm; height, cm) were filled withupland field soil, and the seeds of japanese millet, tall morninggloryand velvetleaf were sowed therein and covered with soil. A designatedamount of the test compound formulated in an emulsifiable concentrate asin Formulation Example 2 was diluted with water, and the dilution wassprayed onto the soil surface by means of a small hand sprayer at aspray volume of 1000 liters per hectare. The test plants were grown in agreenhouse for days, and the herbicidal activity was examined. Theresults are shown in Table 6.

                  TABLE 6                                                         ______________________________________                                                    Herbicidal activity                                                                            Tall                                             Compound  Dosage  Japanese   morning-                                                                             Velvet-                                   No.       (g/ha)  millet     glory  leaf-                                     ______________________________________                                         1        2000    10         10      7                                                   500    10         10      7                                         2        2000    10         10     10                                                   500    10         10     10                                         3        2000    10         10     10                                                   500    10         10     10                                         4        2000    10         10     10                                                   500    10         10     10                                         5        2000     7          7      7                                         7        2000     9         10      7                                         8         500     9         10     10                                         9         500     7          8      7                                        10         500    10         10     10                                        11         500    10         10     10                                        12         500    10         10     10                                        13         500    10         10     10                                        15        2000     9          9      8                                                   500     9          8      8                                        16        2000     9         10     --                                        18        2000    10         10     10                                        23         500     9          9      8                                        25        2000     9         10      7                                        A         2000     7          0      0                                                   500     0          0      0                                        B         2000     0          0      0                                        C         2000     0          0      0                                        ______________________________________                                    

Test Example 2

Cylindrical plastic pots (diameter, 10 cm; height, cm) were filled withupland field soil, and the seeds of japanese millet, morningglory,radish and velvetleaf were sowed therein and cultivated in a greenhousefor 10 days. A designated amount of the test compound formulated in anemulsifiable concentrate as in Formulation Example 2 was diluted withwater containing a spreading agent, and the dilution was sprayed overthe foliage of the test plant by means of a small hand sprayer at aspray volume of 1000 liters per hectare. The test plants were furthergrown in the greenhouse for 20 days, and the herbicidal activity wasexamined. The results are shown in Table 7.

                  TABLE 7                                                         ______________________________________                                                   Herbicidal activity                                                Compound                                                                              Dosage   Japanese Morning-      Velvet-                               No.     (g/ha)   millet   glory  Radish leaf-                                 ______________________________________                                         1      2000     9        10     10     9                                             500      9        10     10     8                                      2      2000     9        10     10     10                                            500      9        10     10     10                                            125      9        10     10     10                                     3      2000     9        10     10     9                                             500      9        10     10     9                                             125      8        10      9     9                                      4      2000     9        10     10     10                                            500      9        10     10     10                                            125      9        10     10     10                                     7      2000     9         9     10     7                                             500      9         9     10     7                                      8      500      9         9     10     9                                             125      9         9     10     9                                      9      500      9        10     10     9                                     10      500      9        10     10     10                                            125      9        10     10     10                                    11      500      9        10     10     9                                     12      500      10       10     10     10                                            125      10       10     10     10                                    13      500      10       10     10     10                                            125      9        10     10     10                                    14      2000     --        9     10     --                                    15      2000     10        9     10     9                                             500      10       10     10     9                                     16      2000     10        9     10     8                                             500      9        10     10     7                                     17      2000     10        9     10     7                                     18      2000     10       10     10     8                                     19      2000     10       10     10     7                                     20      2000     9        10      9     7                                     21      2000     --       10     --     --                                    22      2000     10       10     10     10                                            500      7        10      9     10                                    23      500      10       10     10     8                                             125      9        10     10     8                                     25      2000     9        10     10     10                                            500      7        10     10     7                                     A       2000     9         2      1     0                                             500      3         1      0     0                                     B       2000     1         3      0     0                                             500      0         1      0     0                                     C       2000     0         2      1     0                                             500      0         1      0     0                                     ______________________________________                                    

Test Example 3

Cylindrical plastic pots (diameter, 8 cm; height, cm) were filled withpaddy filed soil, and the seeds of barnyardgrass (Echinochloa oryzicola)and hardstem bulrush (Scirpus juncoides) were sowed in 1 to 2 cm depth.Water was poured therein to make a flooded condition, and rice Seedlingsof 2-leaf stage were transplanted therein, and the test plants weregrown in a greenhouse. Six days (at that time seeds began to germinate)thereafter, a designated amount of the test compound formulated in anemulsifiable concentrate as in Formulation Example 2 and diluted withwater (2.5 ml) was applied to the pots by perfusion. The test plantswere grown for an additional 19 days in the greenhouse, and theherbicidal activity and phytotoxicity were examined. The results areshown in Table 8.

                  TABLE 8                                                         ______________________________________                                                           Herbicidal activity                                        Compound Dosage  Phytotoxicity                                                                             Barnyard-                                                                             Hardstem                                 No.      (g/ha)  Rice plant  grass   bulrush                                  ______________________________________                                        1         63     1           9       9                                        4         63     1           10      8                                        9         63     0           7       7                                        14       250     0           8       7                                        18        16     1           9       9                                        A        250     0           7       3                                                  63     0           2       0                                        B        250     0           0       0                                        C        250     0           0       0                                        ______________________________________                                    

Test Example 4

Vats (33 cm×23 cm×11 cm) were filled with upland field soil, and theseeds of cotton, tall morningglory, black nightshade, giant foxtail,barnyardgrass and johnsongrass were sowed therein 1 to 2 cm depth. Adesignated amount of the test compound formulated in an emulsifiableconcentrate as in Formulation Example 2 was diluted with water, and thedilution was sprayed onto the soil surface by means of a small handsprayer at a spray volume of 1000 liters per hectare. The test plantswere grown in a greenhourse for 20 days, and the herbicidal activity andphytotoxicity were examined. The results are shown in Table 9.

                  TABLE 9                                                         ______________________________________                                                   Herbicidal activity                                                      Dos-           Tall                                                     Com-  age    Phyto-  morn- Black       Barn- John-                            pound (g/    toxicity                                                                              ing-  night-                                                                              Giant yard- son-                             No.   ha)    Cotton  glory shade foxtail                                                                             grass grass                            ______________________________________                                         1    500    0       10    10    10    10    10                                2    500    0       10    10    10    10    8                                 3    500    0       10    9     10    10    8                                 7    500    0       10    --    10    9     8                                 8    500    0       10    10    10    9     8                                 9    500    0       8     7     10    7     7                                10    500    0       10    9     10    10    10                               11    500    0       10    --    10    10    10                               15    250    0       7     7      9    7     8                                16    500    0       7     8     10    8     10                               18    250    0       7     7     10    7     9                                25    500    0       7     10     9    7     --                               A     500    0       0     0      6    6     0                                B     500    0       0     0      0    0     0                                C     500    0       0     0      0    0     0                                ______________________________________                                    

Test Example 5

Wagner's pots (1/5000 are) were filled with paddy field soil, and theseeds of barnyardgrass (Echinochloa oryzicola) and broad-leaved weeds(i.e., common falsepimpernel, indian toothcup, waterwort, Ammanniamultiflora) were sowed in 1 to 2 cm depth. Water was poured therein tomake a flooded condition, and rice seedling of 3-leaf stage weretransplanted therein, and the teast plants were grown in a greenhouse.Five days (at that time barnyardgrass began to germinate) thereafter, adesignated amount of the test compound formulated in an emulsifiableconcentrate as in Formulation Example 2 and diluted with water (10 ml)was applied to the pots by perfusion. The test plants were grown for anadditional 19 days in the greenhouse, and the herbicidal activity andphytotoxicity were examined. The results are shown in Table 10. At thetime of the treatment, the depth of water in the pots was kept at 4 cmand following two days, water was let leak a volume corresponding to a 3cm depth per day.

                  TABLE 10                                                        ______________________________________                                                           Herbicidal activity                                                                              Broad-                                  Compound Dosage   Phytotoxicity                                                                            Barnyard-                                                                              leaved                                  No.      (g/ha)   Rice plant grass    weeds                                   ______________________________________                                         2       63       1          9        9                                        7       63       0          9        10                                       8       16       0          9        10                                       9       63       0          9        10                                               16       0          8        8                                       11       16       0          10       --                                      12       16       0          7        9                                       13       16       1          7        10                                      14       250      0          8        --                                      15       63       1          10       10                                      16       63       1          8        9                                                16       0          8        7                                       19       250      1          10       10                                               63       0          8        7                                       20       250      1          8        10                                      22       63       0          9        --                                      23       16       1          9        --                                      25       250      1          10       10                                               63       0          9        8                                       A        250      0          7        0                                                63       0          0        0                                       B        250      0          0        0                                       C        250      0          0        0                                       ______________________________________                                    

Test Example 6

Vats (33 cm×23 cm×11 cm) were filled with upland field soil, and theseeds of persian speedwell and wheat were sowed therein 1 to 2 cm depth.A designated amount of the test compound formulated in an emulsifiableconcentrate as in Formulation Example 2 was diluted with water, and thedilution was sprayed onto the soil surface by means of an automaticsprayer at a spray volume of 1000 liters per hectare. The test plantswere grown in a greenhourse for 25 days, and the herbicidal activity andphytotoxicity were examined. The results are shown in Table 11.

                  TABLE 11                                                        ______________________________________                                        Compound Dosage   Phytotoxicity                                                                             Herbicidal activity                             No.      (g/ha)   Wheat       Persian speedwell                               ______________________________________                                        1         32      0           10                                              2         32      0           10                                              4         32      0            9                                              7         32      0            7                                              8         32      0           10                                              9        125      0           10                                              15       250      1           10                                              16       250      0           10                                              B        250      0            0                                              C        250      0            0                                              ______________________________________                                    

What is claimed is:
 1. An iminothiazoline compound of the formula:##STR28## wherein R¹ is halogen, halo(lower)alkyl, halo(lower)alkoxy orhalo(lower)alkylthio; R⁴ is halogen; and R⁶ is hydrogen or methyl.
 2. Animinothiazoline compound of the formula: ##STR29## wherein R¹ ishalogen, halo (C₁ -C₃)alkyl, halo(C₁ -C₃)alkoxy or halo (C₁-C₃)alkylthio; R⁴ is halogen; and R⁶ is hydrogen or methyl.
 3. Thecompound of claim 1, wherein R¹ is selected from the group consisting oftrifluoromethyl, fluoro, chloro, bromo and trifluoromethoxy; and R⁴ isfluoro or chloro.
 4. The compound of claim 1, wherein R¹ istrifluoromethyl, R⁴ is 4-fluoro and R⁶ is hydrogen.
 5. The compound ofclaim 1, wherein R¹ is trifluoromethyl, R⁴ is 4-chloro and R⁶ ishydrogen.